The Secret World of Squids: Nature's Underwater Marvel

The squid is one of nature's greatest marvels. Despite being one of the simpler members of the animal kingdom, Hashem has gifted it with a series of rare and impressive traits that enable it to survive in harsh living conditions.

An invertebrate marine creature from the mollusk class, the squid shares its lineage with the octopus. While they may seem similar, notable differences exist in both temperament and appearance. A key difference lies in their limbs: the octopus has eight arms (hence its name, deriving from a word for eight), while the squid boasts ten, with two used for hunting. This detail inspired the term "decapod," highlighting its ten appendages at the front of its body.

Additionally, unlike the octopus, which lacks an external shell common to many mollusks, the squid possesses an internal structure dubbed a "gladius," which serves as an internal skeleton. Upon the squid's death, this structure often washes ashore.

The squid's blood circulation is highly developed, as demonstrated by its three hearts. Its nervous system and eyes are also sophisticatedly constructed. Its elongated, cylindrical body is equipped with suction cups scattered along its arms, which assist in capturing prey. Its diet predominantly comprises fish and other mollusks, which it skillfully hunts using its arms.

Ink Defense

The squid's name in Hebrew originates from its defensive behavior in times of distress. When attacked by a swift predator, the squid panics and releases a black, ink-like fluid serving as a diversion. While the predator attends to the dark cloud, seemingly an escaping victim, the squid jets away to safety.

Swift in movement, the squid's method of swimming resembles a jet plane's propulsion. It exhales water through a special siphon near its mouth, a process akin to a plane's thrust, allowing it to effectively evade predators.

Its main enemies include sharks, seals, crocodiles, and especially the common eel, a snake-like fish. A large eel, spanning up to three meters in the Pacific Ocean, can swallow a small squid whole.

The squid’s ability to instantly change color through the expansion and contraction of pigment cells in its skin allows it to blend seamlessly into the water column or rocky seabeds. This adeptness at camouflage not only conceals it from predators but also aids in its predation efforts.

Meet the Giant Squid

Naturalists have identified over one hundred species of squids, ranging in size from a mere 3 cm to over a meter in length. Among them, the "giant squid" stands out, reaching lengths of up to 20 meters (including arms)! Despite their size, our understanding of their lifestyle remains limited. Researchers seeking to study these elusive creatures face the challenge of scarce specimens; only a few hundred giant squids have been collected thus far, making it unclear whether they represent a particular species or encompass several subspecies. The paucity of findings suggests that the ocean may yet conceal unknown, massive squids alongside other wonderous beings waiting to be discovered.

What is known about the giant squid is that its eyes are the largest among all animals, measuring up to 30 cm in diameter. In the perpetually dark deep sea, these enormous eyes are vital, allowing the squid to capture the faintest glimmers of available light.

Its arms are lined with hundreds of suction cups, each affixed on a "stalk" and surrounded by rings of sharp teeth, ensuring a firm grip on prey. By physically attaching to and puncturing its prey's skin, the squid captures its meal. The suction cups range from 2-5 cm in diameter.

An intriguing trait of the giant squid (and other large squid species) is their buoyancy. They float by utilizing ammonia (a colorless, toxic gas) in their tissues, which is less dense than seawater. Lacking the air-filled swim bladder that grants other fish buoyancy, these squids rely on ammonia, rendering them inedible to humans.

Squid Ink Artistry

A different species found in the Mediterranean is known as the chemist's squid. Medium in size, its ink was historically used by artists. About a century ago, the Rebbe of Radzin, of blessed memory, researched it and proposed that this squid might have been the source of the techelet dye used in the Mishkan and tzitzit. However, his theory was not widely accepted among contemporary scholars.

With such distinctive features, the squid ranks among the most wondrous creations between heaven and earth. Its ability to camouflage with "protective colors," achieve jet-like speed to escape predators, create an ink "smokescreen" defense, and its incredibly flexible body all equip it to procure its meals and thrive in its challenging environment.